How much

How much salt for a 180 gallon?

Pre-calculated for the 180 gallon (72 × 24 × 25 in · raw volume ≈ 187 US gal · water volume ≈ 170 US gal).

By scenario

ScenarioAmount
Initial fill (cycling the tank)

56.1 lb (25449 g)

Or about 3.08 × 7 kg buckets / 0.97 × 22 kg buckets.

10% weekly water change

5.62 lb (2550 g)

17 gal new saltwater. Many reefers settle here as a routine.

20% bi-weekly water change

11.24 lb (5100 g)

34.0 gal new saltwater every 2 weeks.

Annual salt budget (10% weekly)

292 lb (132.6 kg)

Plan on 19 × 7 kg buckets per year.

Brands hobbyists actually use

Buckets reefers actually buy at this volume. Coral Pro for high-alk SPS, Pro Reef for low-alk dosing tanks, Reef Crystals for budget mixed reefs.

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Last reviewed